> > Perhaps this explains why 2.1.77 panics on my Alpha? 2.1.76 works fine.
>
> Yes. I have this fixed in my tree, although not the same way as Martin (I
> just moved the new "struct task_struct" entry down to where it belongs),
> which automatically fixes all architectures.
it was put there on purpose in the original patch (which you greatly
improved, leaving almost nothing untouched, except that big fat bug ;), my
thinking was that we access the first cacheline of the task struct when we
enter the system, and this is the time when access checks are done as
well, so the cacheline will be hot. Is there any other ordering logic
behind that stuff? Also, as debug[8] is exactly 1 cacheline, we could
align it on cacheline as well, it gets active only at context switch time,
a few orders less used than the system entry code.
-- mingo